Black-Box is a unique product geared to aircraft enthusiasts who want to monitor all local air traffic or listen to in-flight communications from the cabin - WITHOUT HAVING TO REMEMBER THE FREQUENCIES. It needs no tuning. Just switch on, set squelch level and listen. There are no oscillators to radiate. It is completely passive - just like and MP-3 player. No matter what the AM VHF channel - you will hear it. It will even monitor two signals at once, with NO mutual interference. Use built-in speaker or earpiece provided. No need to know the local operating channels. Works anywhere in the world. Hears all overhead airways traffic. Hears unpublished channels. No ordinary scanner can match its instant monitoring. No other scanner is legal in an aircraft. "I recently traveled halfway round the world with a Black-Box as my companion, touching down in Taipei, Hong Kong, Singapore, Edinburgh and London. I was able to monitor all the flight deck communications, even when the flight deck used box 1 and 2 for simultaneous transmissions - one for air traffic and the other for company traffic. I was able to monitor the aircraft chatting to another company aircraft in the vicinity. It was clear, easy copy, and I had no worries about which frequency was being used. Then on the ground I could monitor all the local traffic. I had no idea of the local channels: I didn't need to. The Black-Box heard everything. In the car, I was able to plug the Black-Box into a cigar socket and let it monitor any local aircraft. It was easy and very effective. Again, no local knowledge of aircraft channels was necessary." What about an antenna? No problem, it uses the earpiece cable.